Olson Daniel W, Dorfman Kevin D
Department of Chemical Engineering and Materials Science, University of Minnesota-Twin Cities, 421 Washington Ave. SE, Minneapolis, Minnesota 55455, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Oct;86(4 Pt 1):041909. doi: 10.1103/PhysRevE.86.041909. Epub 2012 Oct 12.
We used top-down fabrication techniques to create both an ordered hexagonal array and a disordered array of 1 μm diameter cylindrical posts in a silicon dioxide microchannel with the same number of posts per unit area. The electrophoretic mobility and dispersion coefficient of λ DNA in each of the arrays were obtained as a function of the electric field using ensembles of DNA molecules in a double channel device that minimizes experimental artifacts. To deepen our understanding of the transport, we also used fluorescence microscopy to examine the dynamics of single DNA molecules as they interact with the arrays at a fixed value of the electric field. Based on the results of these two types of experiments, we conclude that the electrophoretic mobility is not dependent on the array order but that band broadening in the device is greater in the disordered array.
我们采用自上而下的制造技术，在二氧化硅微通道中创建了直径为1μm的圆柱形柱体的有序六边形阵列和无序阵列，且每单位面积的柱体数量相同。在一个能将实验假象降至最低的双通道装置中，利用DNA分子集合，获得了λ DNA在每个阵列中的电泳迁移率和扩散系数与电场的函数关系。为了加深我们对传输的理解，我们还使用荧光显微镜来检查单个DNA分子在固定电场值下与阵列相互作用时的动力学。基于这两类实验的结果，我们得出结论：电泳迁移率不依赖于阵列顺序，但无序阵列中装置内的谱带展宽更大。
